Mount Index

Mount Index rises to 5,476 feet in the North Cascades region with dramatic granite walls and dense forest cover. The jagged ridges and steep rock faces define the alpine landscape of this area.

The mountain's composition formed more than 140 million years ago as igneous rock on the ocean floor. These ancient oceanic origins were later pushed to the surface through tectonic activity.

Granite from this peak was quarried to build iconic Seattle structures like the Smith Tower. This local stone shaped the region's architecture and connects the mountain directly to the city's development.

Reaching the summit requires technical climbing skills, proper equipment, and good route-finding through several options. The terrain is steep and exposed, so visitors should have alpine experience.

The granite here contains specific mineral compositions that make it particularly suitable for climbing. The crystal structure and surface texture of the stone create excellent conditions for rock climbers.

Location: Washington

Location: King County

GPS coordinates: 47.77448,-121.58070

Latest update: December 11, 2025 11:09